Malicious PDF — malware analysis report

Static analysis result for SHA-256 b17fd6fb75f3c840…

MALICIOUS

PDF

7.5 KB
MD5: 50143076c6d95c0616d8e3b035ee85da SHA-1: c58db5be7dcc67d129f8459bc42deabd46cf9e0d SHA-256: b17fd6fb75f3c840eba8edefc4c7d7c3d67d168c724f82e0bb3873c8045904bc
266 Risk Score

Malware Insights

MITRE ATT&CK
T1059.001 PowerShell T1204.002 Malicious File

The PDF file contains multiple critical heuristic firings indicating exploitation of CVE-2009-4324, CVE-2009-0927, and CVE-2007-5659. These vulnerabilities are leveraged to execute embedded and obfuscated JavaScript. An extracted artifact, 'Js.Exploit.Shellcode-18', further suggests malicious JavaScript execution. The primary intent appears to be the exploitation of these known PDF vulnerabilities to run arbitrary code.

Heuristics 8

  • media.newPlayer — CVE-2009-4324 critical CVE exact CVE_2009_4324
    PDF JavaScript calls media.newPlayer — CVE-2009-4324 is a use-after-free in Adobe Reader's multimedia plugin triggered by media.newPlayer(). Actively exploited as a zero-day in December 2009. (identified after JavaScript deobfuscation)
  • Collab.getIcon — CVE-2009-0927 critical CVE exact CVE_2009_0927
    PDF JavaScript calls Collab.getIcon — CVE-2009-0927 is a stack buffer overflow in Adobe Reader triggered by Collab.getIcon() with a crafted argument. Allows arbitrary code execution. (identified after JavaScript deobfuscation)
  • Collab.collectEmailInfo — CVE-2007-5659 critical CVE exact CVE_2007_5659
    PDF JavaScript calls Collab.collectEmailInfo — CVE-2007-5659 is a buffer overflow in Adobe Reader triggered by a long argument or heap-sprayed message field passed to Collab.collectEmailInfo(). Part of a series of Acrobat JS API exploits. (identified after JavaScript deobfuscation)
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
javascript_obj0039_000.js
373b81d48eacc9ab765bb68611ae0e3d6251159bf052f3c3b433bb10c4bf19a9
pdf-javascript-stream PDF /JS object 39 at offset 0x16F 28098 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
legacy_pdfkit_stage_000.js
d80fbf18a538524687ba090bf14ad3f01057f1d0e56d91873391689b1ed930a6
deobfuscated-js numeric array XOR decoded JavaScript at offset 0x16F 5488 bytes
Detection
ClamAV: Js.Exploit.Shellcode-18
Obfuscation or payload: likely
Carved artifact contains 9 eval/decoder/string-building token(s).
legacy_pdfkit_stage_001.js
fb7e7a5d017875bb9957eaead0af712ef9f86dcca19ac287c65ad8ba2e665743
deobfuscated-js numPages XOR decoded JavaScript at offset 0x16F 5488 bytes